Explosive compositions based upon particulate fuels dispersed in solutions or suspensions of water soluble inorganic oxidizing salts are well known in the art. For example, U.S. Pat. No. 3,456,589 to Thomison et al. discloses a slurry explosive formulated from at least one inorganic oxidizing salt, a non self-detonating fuel, water, a liquid organic fluid extender and usually also a gelling or thickening agent. Gaseous voids provided by hollow glass particles are incorporated into the slurry explosive in order to reduce its density and enhance detonability of the slurry explosive. The particulate metal fuels in the Thomison formulation may be employed either alone or in mixture with other fluids such as carbonaceous fuels. Suitable metallic fuels include aluminum, magnesium, silicon, iron, ferrosilicon, ferrophosphorous and mixtures and alloys of such metals. The particulate metals are employed in sizes ranging from about 8-200 mesh and in amounts up to about 50 wt. %, with about 10-30 wt. % being preferred. Oxidizer salts which may be employed in the Thomison formulation include ammonium, alkali metal and alkaline earth metal nitrates, and perchlorates and mixtures thereof. Liquid fluid extenders disclosed for use in the Thomison formulation include ethylene glycol, propylene glycol, glycerol, formamide and low molecular weight mono-hydroxy alcohols such as methanol. Polymeric thickening agents disclosed in the Thomison patent for use in formulating the slurry explosives include polysaccarides such as gum arabic, guar gum, caraya gum and synthetic polymers such as polyacrylamides and polyvinyl alcohols. In preparing an explosive formulation, a thickening agent is dispersed in propylene glycol followed by the addition of water and formamide. Crushed sodium nitrate and ammonium nitrate are then added, followed by glass microbubbles and particulate aluminum. A cross-linking agent i then added and the explosive composition allowed to gel. U.S. Pat. No. 3,297,502 to Chrisp discloses a water-based explosive incorporating an inorganic oxidizing salt and a particulate metal fuel which is coated in order to protect the metallic particles from the aqueous phase of the explosive formulation. The metallic fuels which are subject to the coating procedure include light elements such as aluminum, magnesium, zinc, boron and silicon and heavier metallic alloys such as ferrophosphorous and ferrosilicon. Coating may be accomplished by using an aliphatic mono-carboxylic acid containing from about 8-22 carbon atoms, together with an oil having a viscosity of about 30-400 SUS at 100.degree. F. Numerous thickening agents are disclosed in Chrisp and include gums, starches, cellulose derivatives such as carboxymethylcellulose, polyacrylamides and partially hydrolyzed polyacrylamides and synthetic biopolymers such as the excellular heteropolysaccaride B-1459. A winter fluidizing (antifreezing) agent can be incorporated in order to enable explosive formulations to retain handling properties down to about -10.degree. F. Fluidizing agents disclosed in Chrisp include ethylene glycol, monoethylether and diethylene glycol as well as various other materials including those disclosed in the Thomison patent.
U.S. Pat. No. 3,765,967 to Funk et al. discloses a slurry explosive comprising finely divided aluminum, having particle sizes such that most will pass through a 325 US sieve, in a salt solution containing about 20-60 wt. % of alkali or alkaline earth metal perchlorate or ammonium perchlorate in a fully dissolved state in a mixture of water and an organic fuel, which may be a diol such as ethylene glycol or a low molecular weight alcohol such as methanol or ethanol or mixtures thereof. Self-explosives may also be employed in the formulation as well as entrapped gas bubbles.
U.S. Pat. No. 4,388,254 to Maes et al. discloses a procedure for making an aqueous slurry-type blasting composition from two separately packaged components. One component comprises a nitrate oxidizer or ammonium nitrate or a mixture of ammonium nitrate with alkali or alkaline earth metal nitrates. The second component comprises a slurry of a finely divided metal such as aluminum in water together with a gelling or thickening agent. The aluminum may include a coating agent to prevent reaction with water. A small amount of a glycol such as propylene glycol is incorporated into the second component in order to aid in dispersing the gelling agent. The two components may be mixed on site together with additional water to provide the explosive composition.